Current second generation and third generation wireless systems are primarily designed to support unicast voice and data services. The support of these unicast services to the end user has been achieved through various advances in wireless and networking technologies. A current emphasis in international standardization bodies such as 3GPP and 3GPP2 is on the design of protocols and procedures that allow the support of Broadcast-Multicast Services over evolving networks. BCMCS is a bandwidth-conserving technology that reduces traffic by simultaneously delivering a single stream of information to a large number of recipients. Examples of these services include voice dispatch or Press-To-Talk (PTT) type services, broadcast/multicast streaming, etc.
There has been recent industry interest in the Public Safety Wireless Network (PSWN) context, where support of BCMCS may be especially important in terms of radio resource management. Radio resource management procedures may be needed to achieve low delay in establishment and delivery of BCMC content, to provide scalability in terms of the number of multicast groups and/or number of users per multicast group, to provide advanced service capabilities (e.g., ability to monitor/extract content from multiple BCMC streams), and to reduce unnecessary traffic on one or both of the forward link (base station to mobile terminal) or reverse link (mobile terminal to base station).
In an effort to reduce traffic on the forward and/or reverse link, the above-described radio resource management procedures may include the transmission of a BCMC Services Parameters Message (BSPM) that indicates currently available services and specifies how to access these services (e.g. frequency, channel, demultiplexing indicators, etc.) on the forward link. Transmission of the BSPM can mitigate the need for mobile terminals to transmit registration messages on the reverse link. For example, if the service is available and parameters specifying how to access the service are included, the mobile terminal can skip registration and immediately access the service. Furthermore, if the BSPM can be transmitted in an efficient manner in the forward link, then the goal to reduce traffic on both the forward and reverse links can be achieved.
The BSPM may be exceedingly long as it may be comprised of many parameters required for the reception of BCMC content, including BCMC flow identifiers, Logical to Physical Mappings (LPM), and neighbor information for each BCMC flow. As a result, there may be several issues regarding BSPM transmission. First, it may be difficult to transmit the full set of BSPM parameters pertaining to all active BCMC flows within a sector (henceforth referred to as a “full BSPM”) in a single transmission given system requirements (e.g. latency requirements to transmit other overhead messages, pages, multi-slot messages, and so forth). In addition, it may be difficult to transmit the full BSPM frequently on a signaling channel with limited capacity. Infrequent transmissions of BSPMs introduce delays that affect the quality of service and in some cases may preclude the ability to support some services due to intolerable delays.